CVE-2021-4463: Shenzhen Longjing Technology Co. Ltd Bems API

High severity, CVSS 8.7. EPSS: 1.5% chance of exploitation in the next 30 days.

Longjing Technology BEMS API versions up to and including 1.21 contains an unauthenticated arbitrary file download vulnerability in the 'downloads' endpoint. The 'fileName' parameter is not properly sanitized, allowing attackers to craft traversal sequences and access sensitive files outside the intended directory.

Affected products

• Shenzhen Longjing Technology Co. Ltd Bems API: up to and including 1.21

Published 2025-11-12. Last modified 2026-06-17.